Tutorial 16/20 — Advanced Logic

Python: Sorting Algorithms

Organising data using the Compare & Swap method. Low-to-high efficiency.

The Hook

How does Netflix rank Top 10 movies? How does Amazon sort price low-to-high?

They use Sorting Algorithms. Computers aren't magic—they just compare two things, and if they're in the wrong order, they SWAP them.

[8, 2, 5] [2, 5, 8]

The Temporary Swap logic. Critical for all sorting.

# Sorting: The Swap

# We want to swap nums[0] and nums[1]

nums = [10, 5, 20]

# 1. Save data to a TEMP space

temp = nums[0] # temp is 10

# 2. Overwrite the first space

nums[0] = nums[1] # nums[0] is 5

# 3. Retrieve from TEMP

nums[1] = temp # nums[1] is 10

Logic Gate

A list contains [8, 2, 5]. Run this logic:

if nums[0] > nums[1]:
  temp = nums[0]
  nums[0] = nums[1]
  nums[1] = temp
print(nums)

Level 43: Bronze

"Finish the logic to swap the first and second items in the list."

nums = [9, 1, 5]
temp = nums[0]
nums[0] = ...
nums[1] = ...
print(nums)

> swap_buffer_standby

Level 44: Silver

"This code only swaps if the first item is SMALLER. Fix the symbol to sort Low-to-High."

nums = [9, 2, 5]
# Currently sorts WRONG
if nums[0] < nums[1]:
    t = nums[0]
    nums[0] = nums[1]
    nums[1] = t
print(nums)

> debugger_comparator_active

Level 45: Gold

Relational Comparison Pattern

> comparison_vector_online